[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Time Skewing on Windows XP

On 3/14/2013 11:06 AM, Jan Beulich wrote:
On 14.03.13 at 16:16, Suravee Suthikulanit<suravee.suthikulpanit@xxxxxxx>  
I finally traced the issue back to the patch that this first happened.  This
bug started in the patch :

H86/HVM: assorted RTC emulation adjustment (w/ git commit id

I believe there are some issues with the changes in rtc_ioport_read in the
arch/x86/hvm/rtc.c and in the pt_update_irq().
One thing you may want to try is remove the call from REG_C
read to rtc_timer_update() again - on a second thought it may
be wrong to do it here, as (other than check_update_timer()
and alarm_timer_update()) the function doesn't change with
RTC_PF getting cleared (i.e. I may have wrongly added the call
in analogy to the other two).
If I do the followings, things start working again:
1. remove the rtc_timer_update() in the rtc_ioport_read()
2. Revert back the "rtc_periodic_cb()" and remove the "rtc_periodic_interrupt()"

What was the purpose of changing the "rtc_periodic_cb()" to "rtc_periodic_interrupt()" ?

I would expect the issue to be that create_periodic_time()
pointlessly destroys and then recreates an identical rate timer.

I'm puzzled though that some Windows versions depend on
the RTC to maintain their wall clock time...


Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.